Quiz - Structure and Reactivity - 1 | Structure and Reactivity

Organic Chemistry 1 - Quiz - Structure and Reactivity - 1

1

Which compound is most acidic?

When comparing the acidity of different molecules, it is actually easier to compare the stability of their respective bases ⇒ less stable base = strongest base ⇒ strongest base = weakest acid

The more electronegative an atom, the stronger the inductive attracting effect and the more stable the base
Electronegativity: F > Cl > Br > I

 

2

Which compound is most basic?

Lone pairs of electrons are stabilized by the s character of orbital. The % of s character is 25% in sp3 hybridization, 33% in sp2 and 50% in sp. Therefore, increasing basicity correlates with hybridization as follows: sp < sp2 < sp3

 

3

Which compound is an ether?

CH3CH2CH2COH ⇒ aldehyde;   CH3CH2CH2COOH ⇒ carboxylic acid;   CH3CH2OCH2CH⇒ ether;   CH3CH2COCH3 ⇒ ketone

4

Which of the following compounds is a Lewis Base?

A Lewis base is a substance that donates an electron pair: H2O has 2 pairs of electrons on oxygen ⇒ it is a Lewis base
A Lewis acid is a substance that accepts an electron pair: BH3 and AlCl3 are electron-poor species (boron and aluminium need electrons to follow the octet rule) ⇒ BH3 and AlCl3 are Lewis acids

5

Which of the following cannot react as a nucleophile?

CH3O+H2 is an electrophile: electron-poor species that can form a covalent bond by accepting an electron pair from a nucleophile. Indeed the oxygen atom is positively charged and therefore poor in electrons

6

How do you call 2 molcules with the same molecular formula but different bonds?

Constitutional isomers:

Chemical species with the same molecular formula but that differ in the way the atoms are connected to each other. They are also called structural isomers.